Problem: Solve for $x$ and $y$ using substitution. ${-4x-2y = -2}$ ${x = -4y+11}$
Since $x$ has already been solved for, substitute $-4y+11$ for $x$ in the first equation. ${-4}{(-4y+11)}{- 2y = -2}$ Simplify and solve for $y$ $16y-44 - 2y = -2$ $14y-44 = -2$ $14y-44{+44} = -2{+44}$ $14y = 42$ $\dfrac{14y}{{14}} = \dfrac{42}{{14}}$ ${y = 3}$ Now that you know ${y = 3}$ , plug it back into $\thinspace {x = -4y+11}\thinspace$ to find $x$ ${x = -4}{(3)}{ + 11}$ $x = -12 + 11$ ${x = -1}$ You can also plug ${y = 3}$ into $\thinspace {-4x-2y = -2}\thinspace$ and get the same answer for $x$ : ${-4x - 2}{(3)}{= -2}$ ${x = -1}$